Zivoli Rosanna, Gambacorta Lucia, Piemontese Luca, Solfrizzo Michele
Institute of Sciences of Food Production (ISPA), National Research Council of Italy (CNR), Via Amendola 122/O, Bari 70126, Italy.
Toxins (Basel). 2016 Jan 19;8(1):26. doi: 10.3390/toxins8010026.
The efficacy of color sorting on reducing aflatoxin levels in shelled apricot kernels was assessed. Naturally-contaminated kernels were submitted to an electronic optical sorter or blanched, peeled, and manually sorted to visually identify and sort discolored kernels (dark and spotted) from healthy ones. The samples obtained from the two sorting approaches were ground, homogenized, and analysed by HPLC-FLD for their aflatoxin content. A mass balance approach was used to measure the distribution of aflatoxins in the collected fractions. Aflatoxin B₁ and B₂ were identified and quantitated in all collected fractions at levels ranging from 1.7 to 22,451.5 µg/kg of AFB₁ + AFB₂, whereas AFG₁ and AFG₂ were not detected. Excellent results were obtained by manual sorting of peeled kernels since the removal of discolored kernels (2.6%-19.9% of total peeled kernels) removed 97.3%-99.5% of total aflatoxins. The combination of peeling and visual/manual separation of discolored kernels is a feasible strategy to remove 97%-99% of aflatoxins accumulated in naturally-contaminated samples. Electronic optical sorter gave highly variable results since the amount of AFB₁ + AFB₂ measured in rejected fractions (15%-18% of total kernels) ranged from 13% to 59% of total aflatoxins. An improved immunoaffinity-based HPLC-FLD method having low limits of detection for the four aflatoxins (0.01-0.05 µg/kg) was developed and used to monitor the occurrence of aflatoxins in 47 commercial products containing apricot kernels and/or almonds commercialized in Italy. Low aflatoxin levels were found in 38% of the tested samples and ranged from 0.06 to 1.50 μg/kg for AFB₁ and from 0.06 to 1.79 μg/kg for total aflatoxins.
评估了颜色分选对降低带壳杏仁中黄曲霉毒素水平的效果。将自然污染的杏仁提交给电子光学分选机，或者进行漂烫、去皮并人工分选，以从健康杏仁中目视识别并分选变色的杏仁（深色和有斑点的）。从这两种分选方法获得的样品进行研磨、匀质化处理，并通过高效液相色谱 - 荧光检测器（HPLC - FLD）分析其黄曲霉毒素含量。采用质量平衡方法来测量黄曲霉毒素在收集组分中的分布。在所有收集的组分中均鉴定并定量了黄曲霉毒素B₁和B₂，其含量范围为1.7至22,451.5 μg/kg的AFB₁ + AFB₂，而未检测到AFG₁和AFG₂。对去皮杏仁进行人工分选取得了优异的结果，因为去除变色杏仁（占去皮杏仁总数的2.6% - 19.9%）可去除总黄曲霉毒素的97.3% - 99.5%。去皮与对变色杏仁进行目视/人工分离相结合是一种可行的策略，可去除自然污染样品中积累的97% - 99%的黄曲霉毒素。电子光学分选机给出的结果差异很大，因为在剔除的组分（占杏仁总数的15% - 18%）中测得的AFB₁ + AFB₂含量占总黄曲霉毒素的13%至59%。开发了一种改进的基于免疫亲和的HPLC - FLD方法，该方法对四种黄曲霉毒素的检测限较低（0.01 - 0.05 μg/kg），并用于监测意大利市场上47种含有杏仁和/或扁桃仁的商业产品中黄曲霉毒素的存在情况。在38%的测试样品中发现黄曲霉毒素水平较低，AFB₁的含量范围为0.06至1.50 μg/kg，总黄曲霉毒素的含量范围为0.06至1.79 μg/kg。
